[dagit] Adjust run status colors
Make some adjustments to the "run status" dots:
- Create a storybook story for status dots
- Modify colors to be a bit brighter, especially SUCCESS and QUEUED.
- Use a pulsing animation for statuses that are in progress or queued, to make the app feel a little more alive
- Make the default dot size 12px to line up better with 4px-based spacing elsewhere
Test Plan: View storybook and Dagit. Verify that dots are rendering and animating as expected.
Reviewed By: bengotow
Differential Revision: https://dagster.phacility.com/D6413